1
|
Moldovan N, Wang L, Kidane B, Nugent Z, Qing G, Tan L, Buduhan G, Srinathan S, Aliani M, Ahmed N. Non-Invasive Exploration of Metabolic Profile of Lung Cancer with Nuclear Magnetic Resonance Spectroscopy. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.1198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
2
|
Kim J, Balshaw R, Trevena C, Banerji S, Murphy L, Dawe D, Tan L, Srinathan S, Buduhan G, Kidane B, Qing G, Domaratzki M, Aliani M. P2.11-10 Discovery of Potential Biomarkers That Discriminate Early Stage NSCLC from Controls by Non-Targeted Metabolomics Profiling. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.1710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
3
|
Shen L, Wang Y, Qing G, Zhang J, Sun Y, Hu P, Hu W, Wang J, Zhang Z. MRI Radiomics Signature as a Potential Biomarker to Predict Different KRAS Status in Colorectal Cancer Patients and Tumor Cells. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
4
|
Wang J, Lu J, Qing G, Shen L, Sun Y, Ying H, Zhang Z, Hu W. A Novel Deep Learning Based Auto Segmentation For Rectum Tumor On MRI Image. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.1529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
5
|
Luo X, Yang X, Li J, Zou G, Lin Y, Qing G, Yang R, Yao W, Ye X. The procalcitonin/albumin ratio as an early diagnostic predictor in discriminating urosepsis from patients with febrile urinary tract infection. Medicine (Baltimore) 2018; 97:e11078. [PMID: 29995751 PMCID: PMC6076169 DOI: 10.1097/md.0000000000011078] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Discrimination between urosepsis and febrile urinary tract infections is important in therapeutic decision-making to indicate suitable treatments to avoid sepsis-related organ failure. Accurate diagnosis is time-consuming and susceptible to false-positive results. Moreover, patient responses to urosepsis are complex and varied. Therefore, this study aimed to develop a new, early diagnostic predictor that could discriminate between patients with urosepsis and those with febrile urinary tract infections using a combination of initial procalcitonin and albumin levels.We conducted a retrospective study involving 140 patients with febrile urinary tract infections from January 2013 to December 2017. Univariate and multivariate logistic analyses were performed to identify the independent risk factors for differentiating urosepsis from febrile urinary tract infection. A receiver operating characteristic (ROC) curve analysis was conducted to compare the predictive accuracy of the procalcitonin/albumin ratio.Patients in the urosepsis group had higher procalcitonin/albumin ratios compared to those in the febrile urinary tract infection group [2.254 (0.978, 6.299) vs 0.021 (0.004, 0.095); P < .001]. Based on multivariate logistic analysis, the procalcitonin/albumin ratio [adjusted odds ratio (OR) 1.029, 95% confidence interval (CI) 1.013-1.045, P < .001] was an independent predictor of urosepsis, which allowed for differentiation from patients with febrile urinary tract infections. The area under the ROC curve (AUC) for the procalcitonin/albumin ratio was 0.937 (95% CI, 0.894-0.980); P < .001. The sensitivity and specificity of the procalcitonin/albumin ratio cut-off values (>0.44) were 84.62% and 96.00%, respectively. Moreover, in the subset of 65 patients with urosepsis, the procalcitonin/albumin ratio in the uroseptic shock group was higher than in the group of patients without uroseptic shock [5.46 (1.43, 6.58) vs 1.24 (0.63, 4.38); P = .009].Our study demonstrates that the procalcitonin/albumin ratio is an early diagnostic predictor that can discriminate between urosepsis and febrile urinary tract infection. Additionally, in patients with urosepsis, those with higher procalcitonin/albumin ratios were more prone to uroseptic shock. Our findings suggest that the procalcitonin/albumin ratio is a rapid and relatively low-cost biomarker that can be used in clinical practice.
Collapse
Affiliation(s)
| | - Xiang Yang
- Department of Gynecology, Panyu Central Hospital, Guangzhou, China
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Lu J, Wang J, Hu W, Zhang Z, Shen L, Sun Y, Qing G. EP-2131: Deep learning based rectum tumor auto segmentation on MRI T2 image. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)32440-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
|
7
|
Tsao M, Torlakovic E, Bigras G, Wang H, Qing G, Cheung C, Xu Z, Couture C, Ionescu D, Smith A. Establishment of a diagnostic algorithm for ROS1 testing in Canada. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx195.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
8
|
Gan L, Xiu R, Ren P, Yue M, Su H, Guo G, Xiao D, Yu J, Jiang H, Liu H, Hu G, Qing G. Metabolic targeting of oncogene MYC by selective activation of the proton-coupled monocarboxylate family of transporters. Oncogene 2015; 35:3037-48. [PMID: 26434591 DOI: 10.1038/onc.2015.360] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 08/14/2015] [Accepted: 08/24/2015] [Indexed: 12/23/2022]
Abstract
Deregulation of the MYC oncogene produces Myc protein that regulates multiple aspects of cancer cell metabolism, contributing to the acquisition of building blocks essential for cancer cell growth and proliferation. Therefore, disabling Myc function represents an attractive therapeutic option for cancer treatment. However, pharmacological strategies capable of directly targeting Myc remain elusive. Here, we identified that 3-bromopyruvate (3-BrPA), a drug candidate that primarily inhibits glycolysis, preferentially induced massive cell death in human cancer cells overexpressing the MYC oncogene, in vitro and in vivo, without appreciable effects on those exhibiting low MYC levels. Importantly, pharmacological inhibition of glutamine metabolism synergistically potentiated the synthetic lethal targeting of MYC by 3-BrPA due in part to the metabolic disturbance caused by this combination. Mechanistically, we identified that the proton-coupled monocarboxylate transporter 1 (MCT1) and MCT2, which enable efficient 3-BrPA uptake by cancer cells, were selectively activated by Myc. Two regulatory mechanisms were involved: first, Myc directly activated MCT1 and MCT2 transcription by binding to specific recognition sites of both genes; second, Myc transcriptionally repressed miR29a and miR29c, resulting in enhanced expression of their target protein MCT1. Of note, expressions of MCT1 and MCT2 were each significantly elevated in MYCN-amplified neuroblastomas and C-MYC-overexpressing lymphomas than in tumors without MYC overexpression, correlating with poor prognosis and unfavorable patient survival. These results identify a novel mechanism by which Myc sensitizes cells to metabolic inhibitors and validate 3-BrPA as potential Myc-selective cancer therapeutics.
Collapse
Affiliation(s)
- L Gan
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - R Xiu
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - P Ren
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - M Yue
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - H Su
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - G Guo
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - D Xiao
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - J Yu
- Key Laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - H Jiang
- Key Laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - H Liu
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - G Hu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - G Qing
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,Medical Research Institute, Wuhan University, Wuhan, People's Republic of China
| |
Collapse
|
9
|
Guan Q, Ma Y, Aboud L, Weiss CR, Qing G, Warrington RJ, Peng Z. Targeting IL-23 by employing a p40 peptide-based vaccine ameliorates murine allergic skin and airway inflammation. Clin Exp Allergy 2013; 42:1397-405. [PMID: 22925326 DOI: 10.1111/j.1365-2222.2012.04022.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Studies have found that the IL-23/Th17 pathway plays an important role in the pathogenesis of atopic dermatitis (AD) and severe and steroid-resistant asthma. Targeting IL-23/Th17 pathway with monoclonal antibodies (mAb) has been successful in the reduction of skin and airway inflammation in animal models. However, the mAb has a short half-life, requiring repeated administrations. For the long-term suppression of IL-23/Th17 pathway, we have previously developed an IL-23p40 peptide-based virus-like particle vaccine, which induces long-lasting autoantibodies to IL-23. OBJECTIVE We sought to evaluate the effects of this IL-23p40 peptide-based vaccine on the down-regulation of allergic skin and airway inflammation in mice. METHODS Mice were subcutaneously injected three times with the IL-23p40 vaccine, or the vaccine carrier protein or saline as controls. Two weeks later, mice were epicutaneously sensitized with ovalbumin four times at a 2-week interval. One week after the final sensitization, mice were nasally administrated with ovalbumin daily for 3 days. One day later, bronchoalveolar lavage fluids (BALF), sera, lung and skin tissues were obtained and analysed. RESULTS Mice immunized with the vaccine produced high levels of IgG antibodies to IL-23, p40 and IL-12 that in vitro inhibited IL-23-dependent IL-17 production. The numbers of total cells, neutrophils, and eosinophils in BALF were significantly reduced in the vaccine group, compared with controls. The levels of IL-13, IL-5, IL-23 and, IL-17 in BALF and levels of serum ovalbumin-specific IgE, IgG1, and total IgE were also significantly decreased. Histological analysis showed less inflammation of the lung and skin tissues in the vaccine group, compared with controls. CONCLUSION AND CLINICAL RELEVANCE Administration of an IL-23p40 peptide-based vaccine down-regulates allergic skin and airway inflammation, suggesting that this strategy may be a potential therapeutic approach in the treatment of AD and asthma.
Collapse
Affiliation(s)
- Q Guan
- Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, Canada; Department of Immunology, University of Manitoba, Winnipeg, Canada
| | | | | | | | | | | | | |
Collapse
|
10
|
Qing G, Zhang S, Wang N. Recurrent iris prolapse after laser goniopuncture in an open-angle glaucoma patient treated with non-penetrating trabecular surgery. Eye (Lond) 2010; 25:252-3. [PMID: 21102490 DOI: 10.1038/eye.2010.172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
|
11
|
Navaratnam S, Murphy L, Qing G, Demers A, Skliris G, Badiani K, Nowatzki J. Estrogen receptor-beta (ER-beta) expression and non-small cell lung cancer (NSCLC) outcome. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e21092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
12
|
|
13
|
Zhou Y, Ma A, Ma Y, Qing G, Zhang T, Peng Z. Tumour Necrosis Factor Alpha (TNFα) Vaccines in the Downregulation of Bowel Inflammatory Responses in Mice. J Allergy Clin Immunol 2007. [DOI: 10.1016/j.jaci.2006.11.546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
14
|
Abstract
Urocortin, a recently identified peptide of the corticotropin releasing hormone (CRH) peptide family, has potent vasodilatory effects in the human fetal placental circulation in vitro, promoting us to hypothesize that urocortin is produced locally to regulate uteroplacental vascular tone during pregnancy. In the present study, we examined the distribution of urocortin in the human placenta, fetal membranes and uterine tissue at term in the presence and absence of labour, using a urocortin antibody produced in our laboratory and the immunoperoxidase staining method. Immunoreactive (IR)-urocortin was observed in the vascular smooth muscle of the myometrium (n=5), decidual stromal cells, syncytiotrophoblast and amnion epithelium (n=10). No differences in staining intensity for urocortin were detected between tissues obtained in the absence (n=5) or presence (n=5) of labour. Staining intensity for IR-urocortin was greatest in the decidua suggesting this may be a site of urocortin production during pregnancy. Subsequently, we tested urocortin secretion from chorio-decidual cells in vitro, using an immunoblot technique. Positive staining for urocortin was observed in 40 per cent of chorio-decidual cells with 34 per cent of these cells secreting urocortin under basal conditions. Since urocortin was secreted by decidual cells we questioned whether urocortin was present in maternal plasma throughout gestation, using radioimmunoassay. Urocortin was detectable in maternal plasma from 7 weeks of gestation and concentrations did not change as gestation progressed. IR-urocortin in the maternal plasma eluted from a Sephadex G-50 column at the same site as synthetic urocortin and had a calculated retention coefficient (Kd) of 0.44. In summary, this study indicates that urocortin is produced by the decidua during human pregnancy and is detectable in maternal plasma. These data are consistent with the hypothesis that urocortin is produced locally by the decidua and may act to regulate uteroplacental blood flow.
Collapse
Affiliation(s)
- V L Clifton
- Mothers and Babies Research Centre, Department of Endocrinology, John Hunter Hospital, Newcastle, NSW, Australia
| | | | | | | | | | | | | |
Collapse
|
15
|
Bortolussi R, Rajaraman K, Qing G, Rajaraman R. Fibronectin enhances in vitro lipopolysaccharide priming of polymorphonuclear leukocytes. Blood 1997; 89:4182-9. [PMID: 9166862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We investigated the role of humoral factors in lipopolysaccharide (LPS) priming of polymorphonuclear leukocytes (PMN) using cells isolated from adults and from neonates. Plasma from newborn infants had decreased priming activity of adult plasma when mixed with LPS in studies measuring oxidative radical production of PMN after stimulation with a formyl bacterial oligopeptide (fMLP). This marked difference was not caused by LPS binding protein (LBP) because the LBP concentration in newborn and adult plasma were similar (138.4 +/- 12.9 U for adults, and 126.9 +/- 12.1 U for neonates, P = .53). Therefore, we attempted to identify other plasma factors that may contribute to LPS priming of PMN. We identified an LPS priming factor for PMN that is present in plasma, heat stable (56 degrees C for 30 minutes), enhanced by heparin, and concentrated in cold precipitates of plasma. Because these properties resemble those of plasma fibronectin, we assessed the role of fibronectin in LPS priming of PMN. Although fibronectin in phosphate-buffered saline (PBS) had little effect on LPS priming of PMN, fibronectin in combination with other plasma factors appeared to play a role in LPS priming of PMN because (1) removing fibronectin from adult plasma dramatically decreased LPS priming activity from plasma (P < .005), (2) addition of fibronectin to fibronectin-depleted plasma restored its LPS plasma priming activity (P < .05), and (3) neutralizing fibronectin with antibody decreased the LPS priming activity of plasma (60.3 +/- 1.3 v 30.2 +/- 2.2, P < .01). Thus, plasma fibronectin plays a role in LPS priming of PMN in the presence of other factors in plasma.
Collapse
Affiliation(s)
- R Bortolussi
- Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | | | | |
Collapse
|
16
|
Abstract
We have previously shown that polymorphonuclear leukocytes (PMN) from cord blood of normal full-term infants have a decreased priming response to lipopolysaccharide (LPS) compared with PMN of adults. Because the reason for this difference is poorly understood, we compared LPS binding on PMN from adults and newborns by using a photoactivatable iodinated LPS (from Escherichia coli O111:B4), coupled to 2-(p-azidosalicylamido)-1,3'-dithopropionate (LPS-ASD) to covalently link LPS to the PMN membrane. We incubated 2 x 10(4) adult or neonatal PMN with 125I-ASD-LPS (100 ng/ml) together with unlabelled LPS (0 to 100,000 ng/ml) for 20 min at 4 degrees C. The maximum total 125I-ASD-LPS binding to newborn PMN (1,004 +/- 103 cpm) was lower than that binding to adult PMN (3,583 +/- 444 cpm; P < 0.01 with respect to newborn PMN). However, the concentration of unlabelled LPS that displaced 50% of the maximum specifically bound 125I-ASD-LPS was similar for PMN from adult and newborn infants (-4.85 +/- 0.04 and -5.13 +/- 0.14 log g of LPS per ml, respectively; P > 0.05). We further assessed the membrane binding of 125I-ASD-LPS to PMN by using membrane extracts analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. LPS binding proteins were found at approximately 73, 55 to 57, and 25 kDa in both adult and neonatal PMN. However, PMN from newborn infants had markedly lower membrane-associated 125I-ASD-LPS at the 55- to 57- and 25-kDa protein bands as indicated by the intensity of the autoradiograph. Binding of LPS at these bands was specific for the lipid A portion of LPS, since purified unlabelled lipid A displaced 125I-ASD-LPS in a dose-dependent manner. Thus, PMN from newborn infants bind less LPS than do PMN from adults, even though the sites for LPS membrane binding appear to be the same.
Collapse
Affiliation(s)
- G Qing
- Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | | |
Collapse
|
17
|
Qing G, Rajaraman K, Bortolussi R. Diminished priming of neonatal polymorphonuclear leukocytes by lipopolysaccharide is associated with reduced CD14 expression. Infect Immun 1995; 63:248-52. [PMID: 7528732 PMCID: PMC172984 DOI: 10.1128/iai.63.1.248-252.1995] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Previous research in our laboratory has shown that polymorphonuclear leukocytes (PMN) from neonates are not primed effectively in vitro with lipopolysaccharide (LPS) (from Escherichia coli 0111:B4) compared with priming of adult PMN. This finding led us to speculate that differences between neonatal and adult LPS receptors may account for the lower response by neonatal PMN to LPS. In these experiments, we investigated if CD14 or other LPS receptors contribute to the priming activity of PMN by LPS. We found that unprimed neonatal and adult PMN expressed similar numbers of CD14 (11.6 +/- 9.2 versus 18.6 +/- 2.7 fluorescence units [FlU]; P > 0.05) and LPS-binding sites (2.94 +/- 1.4 versus 4.94 +/- 0.79 FlU; P > 0.05). Monoclonal antibody against CD14 (MY4) did not significantly change the binding of LPS to adult unprimed PMN, suggesting that LPS receptors other than CD14 receptors are predominant on PMN. However, when PMN were pretreated with LPS (10 ng/ml) for 45 min at 37 degrees C, expression of CD14 on adult PMN increased to 33.8 +/- 4.9 FlU (P < 0.05 versus unprimed adult PMN) while that on neonatal PMN showed little change, increasing to 17.2 +/- 10.3 FlU (P > 0.05 versus unprimed neonatal PMN; P < 0.05 versus primed adult PMN). Furthermore, MY4 specifically blocked oxidative-radical production from PMN primed with LPS (10 ng/ml) compared with that from control PMN (P < 0.01). These studies suggest that LPS primes PMN by activating CD14 expression. We conclude that lower expression of CD14 or failure to up-regulate CD14 after LPS pretreatment contributes to the inability of neonatal PMN to be primed by LPS.
Collapse
Affiliation(s)
- G Qing
- Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | | |
Collapse
|
18
|
Abstract
The distribution of phenotypes and gene frequencies of the plasminogen were studied in 203 blood donors of the Han population, Chengdu, China using isoelectric focusing followed by immunofixation. The results were as follows: PLGA = 92.12%, PLGAM5 = 4.39%, PLGAB = 1.97%, PLGAB2 = 0.98%. Their gene frequencies were: PLG*A = 0.9606, PLG*M5 = 0.0246, PLG*B = 0.0099, PLG*B2 = 0.0049. This study implied that PLG*M5 might be the specific genetic marker of the Mongoloids.
Collapse
Affiliation(s)
- H Yiping
- Department of Forensic Serology, West China University of Medical Sciences, Chengdu
| | | | | |
Collapse
|
19
|
Abstract
OBJECTIVE The aims were (1) to characterise plasma and tissue atrial natriuretic factor (ANF) levels, haemodynamic variables, and renal function at different stages of moderate chronic high output heart failure in the rat; and (2) to assess the contribution of the atria and ventricles to plasma ANF levels. METHODS Plasma and tissue ANF levels, haemodynamics, and renal function were evaluated at 1, 2, 4, 8, and 16 weeks after the development of aorto-caval shunts. Sham operated animals served as controls at identical time points. Male Sprague-Dawley rats weighing 225-275 g were used in all experiments. RESULTS Mean arterial blood pressure was lower and right atrial pressure was higher in the aorto-caval shunt groups than in sham operated controls at all time periods. Left ventricular end diastolic pressure was increased significantly in aorto-caval shunt rats at 1, 2, and 4 weeks when compared with their control counterparts. Plasma COOH terminal and NH2 terminal ANF concentrations were increased significantly in aorto-caval shunt animals. Plasma ANF was positively correlated with right atrial pressure and left ventricular end diastolic pressure in aorto-caval shunt rats but not in sham operated controls. Aorto-caval shunt animals also developed marked cardiac hypertrophy with decreased atrial ANF concentration, but not content, and increased ventricular ANF concentration and content. Despite high plasma ANF concentrations, aorto-caval shunt rats had a lower packed cell volume at all observed periods and reduced urinary sodium excretion and urinary volume at 1 and 2 weeks, with trends to a reduction at 4, 8, and 16 weeks. Body weight was higher in aorto-caval shunt animals at 16 weeks than in sham operated controls. CONCLUSIONS (1) Chronically increased cardiac filling pressure stimulated not only ANF release but also ANF synthesis in each cardiac chamber, which in turn contributed to raised plasma ANF concentrations in aorto-caval shunt rats; (2) an attenuated renal response to endogenous ANF and sodium and water retention were apparent in A-C shunt rats. Activation of neurohormonal vasoconstrictor systems and gradually decreased plasma ANF concentrations may contribute to sodium and water retention at different stages of this experimental model of heart failure.
Collapse
Affiliation(s)
- G Qing
- Laboratory of Experimental Hypertension and Vasoactive Peptides, Clinical Research Institute of Montreal, Quebec, Canada
| | | |
Collapse
|
20
|
Abstract
We investigated the role of atrial natriuretic factor (ANF) and the renin-angiotensin system as well as the effects of losartan in rats with aortocaval (AC) shunts. Right atrial and left ventricular end-diastolic pressures (LVEDP) were higher and mean arterial blood pressure (MAP) was lower in AC shunt animals than in their controls. AC shunt rats presented marked cardiac hypertrophy, decreased right atrial ANF concentration, and increased ventricular ANF content and concentration. Plasma ANF levels were elevated, and hematocrit was lower in AC shunt animals than in controls. Captopril or losartan treatment decreased MAP and returned LVEDP to sham-operated control values. A clear regression of cardiac hypertrophy was evident in both treated AC shunt groups, with plasma ANF levels tending to follow those in sham-operated rats. Plasma COOH-terminal ANF levels were decreased and urinary volume and hematocrit were increased in losartan-treated AC shunt animals. We conclude that chronic angiotensin converting enzyme inhibition and angiotension II receptor antagonism improved hemodynamic conditions, diminished water retention, reversed cardiac hypertrophy, and restored plasma and tissue ANF to more "normal" levels in rats with moderate high-output heart failure.
Collapse
Affiliation(s)
- G Qing
- Laboratory of Experimental Hypertension and Vasoactive Peptides, Clinical Research Institute of Montreal, Quebec, Canada
| | | |
Collapse
|